/**
 * Copyright (C) 2010 the original author or authors.
 * See the notice.md file distributed with this work for additional
 * information regarding copyright ownership.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.beust.jcommander;

import com.beust.jcommander.converters.CommaParameterSplitter;
import com.beust.jcommander.converters.IParameterSplitter;
import com.beust.jcommander.converters.NoConverter;
import com.beust.jcommander.validators.NoValidator;
import com.beust.jcommander.validators.NoValueValidator;

import java.lang.annotation.Retention;
import java.lang.annotation.Target;

import static java.lang.annotation.ElementType.FIELD;
import static java.lang.annotation.ElementType.METHOD;

@Retention(java.lang.annotation.RetentionPolicy.RUNTIME)
@Target({FIELD, METHOD})
public @interface Parameter {

    /**
     * An array of allowed command line parameters (e.g. "-d", "--outputdir", etc...).
     * If this attribute is omitted, the field it's annotating will receive all the
     * unparsed options. There can only be at most one such annotation.
     */
    String[] names() default {};

    /**
     * A description of this option.
     */
    String description() default "";

    /**
     * Whether this option is required.
     */
    boolean required() default false;

    /**
     * The key used to find the string in the message bundle.
     */
    String descriptionKey() default "";

    /**
     * How many parameter values this parameter will consume. For example,
     * an arity of 2 will allow "-pair value1 value2".
     */
    int arity() default -1;

    /**
     * If true, this parameter is a password and it will be prompted on the console
     * (if available).
     */
    boolean password() default false;

    /**
     * The string converter to use for this field. If the field is of type <tt>List</tt>
     * and not <tt>listConverter</tt> attribute was specified, JCommander will split
     * the input in individual values and convert each of them separately.
     */
    Class<? extends IStringConverter<?>> converter() default NoConverter.class;

    /**
     * The list string converter to use for this field. If it's specified, the
     * field has to be of type <tt>List</tt> and the converter needs to return
     * a List that's compatible with that type.
     */
    Class<? extends IStringConverter<?>> listConverter() default NoConverter.class;

    /**
     * If true, this parameter won't appear in the usage().
     */
    boolean hidden() default false;

    /**
     * Validate the parameter found on the command line.
     */
    Class<? extends IParameterValidator> validateWith() default NoValidator.class;

    /**
     * Validate the value for this parameter.
     */
    Class<? extends IValueValidator> validateValueWith() default NoValueValidator.class;

    /**
     * @return true if this parameter has a variable arity. See @{IVariableArity}
     */
    boolean variableArity() default false;

    /**
     * What splitter to use (applicable only on fields of type <tt>List</tt>). By default,
     * a comma separated splitter will be used.
     */
    Class<? extends IParameterSplitter> splitter() default CommaParameterSplitter.class;

    /**
     * If true, console will not echo typed input
     * Used in conjunction with password = true
     */
    boolean echoInput() default false;

    /**
     * If true, this parameter is for help. If such a parameter is specified,
     * required parameters are no longer checked for their presence.
     */
    boolean help() default false;
}
